Tìm `x in R` biết: `(x+1)/2018 + (x+2)/2017 + (x+3)/2016 = (3x+12)/2015` 14/08/2021 Bởi Sadie Tìm `x in R` biết: `(x+1)/2018 + (x+2)/2017 + (x+3)/2016 = (3x+12)/2015`
Đáp án + Giải thích các bước giải: `(x+1)/(2018)+(x+2)/(2017)+(x+3)/(2016)=(3x+12)/(2015)` `=>(x+1)/(2018)+(x+2)/(2017)+(x+3)/(2016)=(x+4)/(2015)+(x+4)/(2015)+(x+4)/(2015)` `=>((x+1)/(2018)+1)+((x+2)/(2017)+1)+((x+3)/(2016)+1)=((x+4)/(2015)+1)+((x+4)/(2015)+1)+((x+4)/(2015)+1)` `=>((x+1)/(2018)+(2018)/(2018))+((x+2)/(2017)+(2017)/(2017))+((x+3)/(2016)+(2016)/(2016))=((x+4)/(2015)+(2015)/(2015))+((x+4)/(2015)+(2015)/(2015))+((x+4)/(2015)+(2015)/(2015))` `=>(x+2019)/(2018)+(x+2019)/(2017)+(x+2019)/(2006)=(x+2019)/(2015)+(x+2019)/(2015)+(x+2019)/(2015)` `=>(x+2019)/(2018)+(x+2019)/(2017)+(x+2019)/(2006)-(x+2019)/(2015)-(x+2019)/(2015)-(x+2019)/(2015)=0` `=>(x+2019)((1)/(2018)+(1)/(2017)+(1)/(2016)-(1)/(2015)-(1)/(2015)-(1)/(2015))=0` Vì `(1)/(2018)+(1)/(2017)+(1)/(2016)-(1)/(2015)-(1)/(2015)-(1)/(2015)\ne0` `=>x+2019=0` `=>x=-2019` Bình luận
Đây nha bn
Đáp án + Giải thích các bước giải:
`(x+1)/(2018)+(x+2)/(2017)+(x+3)/(2016)=(3x+12)/(2015)`
`=>(x+1)/(2018)+(x+2)/(2017)+(x+3)/(2016)=(x+4)/(2015)+(x+4)/(2015)+(x+4)/(2015)`
`=>((x+1)/(2018)+1)+((x+2)/(2017)+1)+((x+3)/(2016)+1)=((x+4)/(2015)+1)+((x+4)/(2015)+1)+((x+4)/(2015)+1)`
`=>((x+1)/(2018)+(2018)/(2018))+((x+2)/(2017)+(2017)/(2017))+((x+3)/(2016)+(2016)/(2016))=((x+4)/(2015)+(2015)/(2015))+((x+4)/(2015)+(2015)/(2015))+((x+4)/(2015)+(2015)/(2015))`
`=>(x+2019)/(2018)+(x+2019)/(2017)+(x+2019)/(2006)=(x+2019)/(2015)+(x+2019)/(2015)+(x+2019)/(2015)`
`=>(x+2019)/(2018)+(x+2019)/(2017)+(x+2019)/(2006)-(x+2019)/(2015)-(x+2019)/(2015)-(x+2019)/(2015)=0`
`=>(x+2019)((1)/(2018)+(1)/(2017)+(1)/(2016)-(1)/(2015)-(1)/(2015)-(1)/(2015))=0`
Vì `(1)/(2018)+(1)/(2017)+(1)/(2016)-(1)/(2015)-(1)/(2015)-(1)/(2015)\ne0`
`=>x+2019=0`
`=>x=-2019`